Record stamper playback turntable
US4153257A · kind A · utility
5Cited by
3References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1977 |
| Grant date | May 8, 1979 |
| Priority date | — |
| Expiry date | Oct 11, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B23/505
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A turntable to enable playback of record matrices and stampers is provided. The turntable rotates in the direction opposite that of a conventional turntable and is provided with a tone arm carrying a stylus designed to ride the ridges of the stamper. Magnetic members on the table support surfaces hold the stamper flat to prevent "oil canning". The magnetic poles of the members are oriented radially to minimize the effect of the magnetic members on the turntable transducer. The tracking force of the tone arm is variable by means of a sliding weight.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.